great fuel debate
 

hiys boys & girls,
ive always been brought up that supermarket fuel aint as good as other more well known brands such as bp,esso etc etc

however a couple of people have told me just recently that its the same petrol that goes to supermarkets,its just in different tankers ???

anyone got any feedback please

jaymz

It all comes from the same refineries, but the oil companies add different additives. At the end of the day when it comes to performance nothing beats the RON (the octane equivalent number, neat octane = 100)

Standard premium unleaded has RON of 95
Shell Optimax = 97 RON
Super unleaded can vary, Tesco = 99 RON

If you are really worried you can add proprietry fuel cleaners to your fuel- things like Redex etc

I have played around a number of cleaners and other additives over probably 2 years and found none have made any difference to performance or consumption (I have recorded the info and tried to spot trends, but nothing) I have found only 2 things that have altered the stats - RON and how much I use that loud handle on the RHS of the bars.

When I moved to Tesco 99 RON juice the performance was instantly noticeable and the fuel consumption improved. When I stuck to the speed limits and pretended to be a car the fuel consumption improved even more.

My record so far? 118.9 miles on 8.74 litres of fuel which I make to be 61.8 mpg or 231 miles to the tank full.

Do I sound boring? Yes! Does this take a lot of time? Not when you do 300 - 700 miles every week!

Are you telling us that Tesco Super Unleaded beats Shell Optimax :shock: :?

or have i just slipped into a parallel forum :?:

Looks like he is saying that, I noticed a difference when i had a stint using optimax, seemed to last just that bit much longer.

Not tried that Tesco's stuff, will have to give it a go next time I fill up.

Me too if thats the case.

I used Shell V-Power in Germany and that was 100 ron, that sure is gooood stuff.

interesting - i always get fuel from tesco and i always use the cheap stuff. Sounds like spending a few extra pennies might be worthwhile.

Although Tesco Super is 2p a litre more I got that back in consumption!

I have never noticed any difference or documented any consistently better fuel economy with higher octane. I run the cheapest I can get, anything more than what suzuki recommends is a waste of money

This is consistent with the theory. Engines have to be adjusted to get any advantage from higher octane fuel - and they then cannot run on lower octane stuff. Still, i'll give it a go and see what i think. It may be due to other additives they put in more expensive fuels rather than the octane rating.

That again! :lol:

don't confuse octane rating with calorific value (energy content). Octane rating strictly speaking only refers to the tendency to "knock".

However the way the fuel companies get the higher octane ratings nowadays (without the lead) means the fuel usually ends up with a fractionally higher calorific value, but usually less than 2% compared to regular (read 91RON) fuel.

Something like 42.7MJ/kg for 91RON, 43.5MJ/kg for 98RON. You can probably assume 95RON will be somewhere in the middle.

There tends to be a slight increase in density too, so if buying in litres you'll get a fraction more mass for your money.

As simply a fuel benefit you'd be lucky to notice more than a mpg better economy.

Optimising the engine to take advantage of the octane rating, as ophic says, would be worth a bit more.

Having said all that, some engine types are more fuel sensitive than others, and I do use Optimax in my Cappuccino for example since it really does liven up nicely on it. For some reason it just likes the stuff.

I've tried it in other things with varying results. Doesn't seem to make a ha'porth of difference in the Deauville for example, though I still use 98RON etc when on the Continent since it's usually only a cent or 2 more than 95 so you may as well. :?

Try it. If you like the results then use it. If you don't notice any difference, don't waste your money.